First, I suggest that you indicate your location in your profile, very often it helps for people to give you advice that will take in account your climate.
Judging from the plants around the yew (maybe a fuschia on the right and a rhodo on the left), you may live in a place with temparate climate (zone 8) and the soil of your garden may be slightly acidic.
The brick wall, and the colour of the bricks makes me think you perhaps live in northern Europe (England, the north of France, Belgium, the Netherlands,...)
I'm not sure you're a native speaker of English, but maybe you live in the UK anyway, but I'd say the Netherlands.
Signed: Inspector Alain Klouzot.
About this tree:
It's very hazardous to remove so much foliage on a yew when collecting one. My friends say one shouldn't remove 1/3rd to 1/2 of the foliage for a good chance of seiing the tree survive the first winter. Meanwhile, some foliage might remain for a whole season, this doesn't mean the tree is saved. It can live on the energy stored in the tissues for several months, just like cut flowers in a vase can keep for days.
So I'm very pessimistic.
If you're new to bonsai, I'd say too big too soon. It's essential to know more about tree cultivation and the requirements of the species you want to work with before attempting what in your mind would be a "masterpiece". Learn with smaller subects, easier species first.
That's my 2€cents' worth...
PS: your message was posted this morning, Saturday at 11:31 PM
If you posted this message late this morning, how can you expect answers from a community whose members essentially live across the Atlantic: in New York, it's 6 hours earlier (11:50, time for brunch), and in LA, 9 hours earlier (8:50, shower-time) and here, it's 17:50.